1 00:00:00,35 --> 00:00:03,17 We're here at the Polk County Transportation a vision we're going to take 2 00:00:03,18 --> 00:00:07,73 a look to see how the traffic flow is managed back relax and join us on the science 3 00:00:07,73 --> 00:00:07,73 . 4 00:00:23,49 --> 00:00:28,73 Hey we try I mean with Amy the traffic manager for Polk County Amy tell me 5 00:00:28,74 --> 00:00:33,54 a little bit about what you do here while we take care of two hundred in seventy 6 00:00:33,55 --> 00:00:37,65 two signals for the entire county with the exception of the signals in 7 00:00:37,66 --> 00:00:39,28 a city like Lindsay Winter Haven so we have 8 00:00:39,29 --> 00:00:43,60 a big responsibility with traffic signals. Some of those are on state road some of 9 00:00:43,61 --> 00:00:48,34 them are in other cities we have eighty seven of our own signals on county roads 10 00:00:48,35 --> 00:00:54,57 and four those were also responsible to do the signal timings and some of those are 11 00:00:54,58 --> 00:01:00,38 individual time some of them are coordinated traffic signals and do you regulate 12 00:01:00,39 --> 00:01:04,39 that I mean you do plan all that ahead of time is it on the fly is it how does it 13 00:01:04,40 --> 00:01:06,79 work and you know it's kind of case by case when 14 00:01:06,80 --> 00:01:12,57 a new traffic so much goes in we collect traffic data and the timings are based on 15 00:01:12,58 --> 00:01:17,27 the traffic flows on the two roads. We also periodically look at them if we get 16 00:01:17,28 --> 00:01:19,50 a complaint from a citizen if we haven't looked at a signal in 17 00:01:19,51 --> 00:01:22,86 a number of years we'll see if the traffic has changed over time and if any 18 00:01:22,87 --> 00:01:27,38 adjustments need to be made to those timings and what's the purpose or objective of 19 00:01:27,39 --> 00:01:32,19 all this timing the purpose is to get the most efficient flow of traffic we want to 20 00:01:32,20 --> 00:01:37,81 make sure primarily that the major road gets the appropriate amount of time to get 21 00:01:37,82 --> 00:01:41,40 traffic moving through our major corridors and then still provide time for the side 22 00:01:41,41 --> 00:01:46,82 streets to be able to get out and heavy traffic. When we have several signals that 23 00:01:46,83 --> 00:01:50,81 are close together and that's that's more urbanized areas then we're able to 24 00:01:51,00 --> 00:01:54,60 coordinate those times so that one signal will turn in the next one will turn and 25 00:01:54,61 --> 00:01:55,01 you can have 26 00:01:55,02 --> 00:01:59,63 a steady progression of traffic now when you say you regulate in the manage the 27 00:01:59,64 --> 00:02:03,34 timing can you do all that here or how does that work we can't do all of it here 28 00:02:03,35 --> 00:02:06,33 some of it we have to do in the field but we are able to adjust about 29 00:02:06,34 --> 00:02:09,62 a third of our traffic signals from our Traffic Management Center and we can go see 30 00:02:09,63 --> 00:02:12,89 Mike my network analyst and I'll show you how that gets done also will go up. 31 00:02:18,96 --> 00:02:22,08 In my house a guy he sent me this way said you could give me 32 00:02:22,09 --> 00:02:27,80 a little background on as to how you control everything how you can manage and see 33 00:02:27,81 --> 00:02:32,48 it from the cameras and stuff like that all right this is our C.M.C. 34 00:02:32,68 --> 00:02:38,27 And we have ninety three intersections that we can communicate with. That our 35 00:02:38,28 --> 00:02:42,40 central software is up here and that tells us everything that we need to be able to 36 00:02:42,41 --> 00:02:49,08 tell from the controller. Anything that we can do from the field. That's not 37 00:02:49,09 --> 00:02:52,44 mechanical we can do from mere facts logic base we can run it through the computer 38 00:02:52,70 --> 00:02:57,80 OK And you can access I see several streets I'm familiar with you can access all 39 00:02:57,81 --> 00:03:00,33 those just right here in C. 40 00:03:00,34 --> 00:03:02,72 Then at different times or we have 41 00:03:02,73 --> 00:03:07,97 a twenty cameras on our system and of those we can bring them up and we can pan 42 00:03:07,98 --> 00:03:12,12 tilt zoom and we can be able to troubleshoot anything that comes in immediately as 43 00:03:12,13 --> 00:03:15,94 it happens rather than have to send somebody out there if it's an hour away the 44 00:03:15,95 --> 00:03:19,62 conditions may have changed by the time we get to it so this helps us immensely 45 00:03:19,67 --> 00:03:26,06 with the response time and I'm guessing you can just sort of. Focus in on just one 46 00:03:26,07 --> 00:03:30,67 camera see if that's where your problem areas we can the screens we can adjust you 47 00:03:30,68 --> 00:03:34,26 know however we need to we can fit more of them on there make it smaller is to get 48 00:03:34,27 --> 00:03:37,55 more of them on there so you can have one if you're primarily concerned with one 49 00:03:37,56 --> 00:03:40,78 specific incident you can bring one up there and make sure you can get 50 00:03:40,79 --> 00:03:43,83 a good picture of what you're trying to find Now how many cameras do you usually 51 00:03:43,84 --> 00:03:47,16 have it's not an idea of one facing every direction or is it just one that you 52 00:03:47,17 --> 00:03:52,22 control and turning around as you please for these cameras it's just one dome 53 00:03:52,23 --> 00:03:55,81 camera on one of the corner so that usually is the cabinet corners or wherever we 54 00:03:55,82 --> 00:04:00,89 can get the best visibility out of it now looking at video from all over the county 55 00:04:00,90 --> 00:04:05,82 it looks like how do you receive this information is it just Internet we have 56 00:04:05,86 --> 00:04:09,41 a couple different transmission methods that we use for getting only for mission 57 00:04:09,42 --> 00:04:14,44 back here we use fiber where we can get it and that would be ideal but one of the 58 00:04:14,45 --> 00:04:18,34 big challenges of full county is we're so spread out and we aren't close like 59 00:04:18,35 --> 00:04:24,99 a lot of the municipalities we cover all of unincorporated. So on the locations 60 00:04:24,100 --> 00:04:28,95 that we can get fiber we would love that if we can't we use different ways to get 61 00:04:28,96 --> 00:04:32,84 it back here we have some radio shops and some of these camera feeds are coming 62 00:04:32,85 --> 00:04:37,97 over radio and they do just fine for what we need and for we also have some air 63 00:04:37,98 --> 00:04:42,30 cards as well that will allow us to talk to some of the controllers but they're not 64 00:04:42,31 --> 00:04:46,71 powerful enough to bring any kind of video feed OK. Now I know that some of the the 65 00:04:46,72 --> 00:04:51,80 lights are regulated here how do you determine which ones get sent back here we try 66 00:04:51,81 --> 00:04:55,68 to get as many as we can under our system and obviously we don't have them all yet 67 00:04:55,68 --> 00:05:01,94 . But we already talked about the different controllers the older technology in the 68 00:05:01,95 --> 00:05:06,81 newer technology only the newer ones can communicate back to the system anyway so 69 00:05:07,78 --> 00:05:13,27 as we upgrade those older systems we also look at communicating with them at that 70 00:05:13,28 --> 00:05:18,80 time and how do we get that back to here so we try to get as much as possible if 71 00:05:18,81 --> 00:05:23,86 there are clustered together we can try and get as many one time that we can get OK 72 00:05:24,30 --> 00:05:28,28 now I've been I've been on some roads and I've noticed that you hit it just right 73 00:05:28,29 --> 00:05:31,65 and you get the greens just all the way you guys have 74 00:05:31,66 --> 00:05:35,69 a part and that is part of the chord in that system and that is something that we 75 00:05:35,73 --> 00:05:41,23 manage from here. When it shows that it's in coordination and it's in sync you'll 76 00:05:41,24 --> 00:05:45,35 get that good flow occasionally though they do get out of sync and that's one of 77 00:05:45,36 --> 00:05:48,64 the things that we can handle as well OK And how do you handle that you just 78 00:05:49,24 --> 00:05:53,54 a little bit of reprogramming or there's different methods of getting them back in 79 00:05:53,55 --> 00:05:55,22 sync you can go a little bit shorter 80 00:05:55,23 --> 00:05:58,41 a little bit long. The reason they get out of sync is 81 00:05:58,42 --> 00:06:01,84 a lot of times you'll have pedestrian come up on the side and they need 82 00:06:01,85 --> 00:06:06,28 a lot of time to be able to walk and the Don't Walk the clearance time for them as 83 00:06:06,29 --> 00:06:09,94 well and another issue is an ambulance or 84 00:06:10,11 --> 00:06:12,27 a police officer will come through that also in 85 00:06:12,28 --> 00:06:15,37 a coordinated system off as they travel through it or even 86 00:06:15,38 --> 00:06:18,30 a train that comes up as well now I'm 87 00:06:18,31 --> 00:06:23,58 a C N N On this map here with all the other little dots is this I sort of keep an 88 00:06:23,59 --> 00:06:28,23 eye on them to see if they're in sync or out of sync or it is there's several 89 00:06:28,24 --> 00:06:34,16 coordinated systems through ways on here. And even some of them changed or six in 90 00:06:34,17 --> 00:06:39,10 this one includes some of like when and some for county and it doesn't matter who's 91 00:06:39,11 --> 00:06:43,91 system is on as long as it's time based they will sing together so they run pretty 92 00:06:43,92 --> 00:06:48,08 smoothly they're going to wear. Now is there anything else you you can control and 93 00:06:48,09 --> 00:06:51,98 here you program in here other than just the sinking of the lights we can with 94 00:06:51,99 --> 00:06:57,33 a lot of the newer technology we can bring the detection methods and. Everything 95 00:06:57,34 --> 00:06:59,15 back into here one of those 96 00:06:59,16 --> 00:07:04,64 a video detection. And we bring that up in here to map out zones that we don't want 97 00:07:04,71 --> 00:07:08,03 anything interfering with the detection and we don't want you know shadows and 98 00:07:08,04 --> 00:07:12,78 trees and things to negatively affect the intersection and that's one of the 99 00:07:12,83 --> 00:07:19,50 technologies that he's going to talk about in our signal. So 100 00:07:19,54 --> 00:07:22,53 Amy I'm seeing a lot of equipment here there seems to be 101 00:07:22,54 --> 00:07:25,24 a lot of stuff that goes into this can you give me 102 00:07:25,25 --> 00:07:29,98 a little explanation as to what it is sir this is pretty much the brains behind the 103 00:07:29,99 --> 00:07:33,48 whole traffic signal operation you'll see 104 00:07:33,52 --> 00:07:37,54 a cabinet like this and pretty much it every signal is intersection it might be 105 00:07:37,55 --> 00:07:42,07 different we've got some tall skinny ones but this is basically the computer that 106 00:07:42,08 --> 00:07:45,76 operates the signal and all the timings right now I see a lot 107 00:07:45,77 --> 00:07:51,50 a lot of technology in here is it always been this way now years ago traffic 108 00:07:51,51 --> 00:07:55,64 signals were operated by a a mechanical system that only could have 109 00:07:55,65 --> 00:07:58,40 a fixed time so there was a certain time for the main road 110 00:07:58,41 --> 00:08:03,28 a certain time for the side road but now we have computerized equipment that we can 111 00:08:03,29 --> 00:08:08,83 adjust times based on the vehicles that are coming so. The controllers smart enough 112 00:08:08,84 --> 00:08:13,96 to know if there's more traffic it's able to give more time to the main street and 113 00:08:13,97 --> 00:08:18,73 if there's no traffic on the main road it'll switch to the side road so that it's 114 00:08:18,77 --> 00:08:19,21 it's gotten 115 00:08:19,22 --> 00:08:24,59 a lot smarter over the years now what is this why don't contrivance you appear it 116 00:08:24,60 --> 00:08:25,09 looks like 117 00:08:25,10 --> 00:08:28,59 a street with actual lights is this what's happening right now because this 118 00:08:28,60 --> 00:08:30,82 controller actually we can test 119 00:08:30,83 --> 00:08:35,26 a controller before we put it out in the field so this hooks up to this board and 120 00:08:35,27 --> 00:08:38,36 the board looks just like it would operate out in 121 00:08:38,37 --> 00:08:41,93 a traffic signal in the field so the lights as you see him changing that's how they 122 00:08:41,94 --> 00:08:46,04 change based on the times are programmed in this controller right. Now OK So this 123 00:08:46,05 --> 00:08:51,85 is it in this is what's actually in those boxes were it is life it is very cool All 124 00:08:51,86 --> 00:08:55,15 right so this is the brains of the operation what are some of the other parts of 125 00:08:55,16 --> 00:08:58,65 the systems I mean what all does it control obviously the law is but how does that 126 00:08:58,66 --> 00:09:04,66 all can measure Well this is the traffic you know this is the computer but there 127 00:09:04,67 --> 00:09:10,86 has detectors that actually receives information from. From the traffic that's 128 00:09:10,87 --> 00:09:15,51 coming we have different ways to detect traffic either inductive loops that are cut 129 00:09:15,52 --> 00:09:16,41 in the ground you may see 130 00:09:16,42 --> 00:09:20,01 a big circle in the pavement where you stop your vehicle that's an inductive loop 131 00:09:20,02 --> 00:09:22,63 it works sort of like a magnet and can tell if 132 00:09:22,64 --> 00:09:26,78 a car's there we also use video detection so we have cameras that can tell us if 133 00:09:26,79 --> 00:09:31,11 the car's there so that it takes that information it knows the car's there and it 134 00:09:31,12 --> 00:09:36,66 feeds it to the computer to tell the controller what to do with the with the 135 00:09:36,67 --> 00:09:41,91 traffic signal OK And so I see that. Turn signals obviously I see that all the time 136 00:09:41,91 --> 00:09:45,46 . Does that control the pacing too I mean if there's 137 00:09:45,47 --> 00:09:51,91 a lot of cars. Depending on the amount of traffic it is able to we have 138 00:09:51,92 --> 00:09:57,46 a minimum time set for how much green time you're going to be allowed but there's 139 00:09:57,47 --> 00:09:57,72 also 140 00:09:57,73 --> 00:10:03,96 a maximum time so if there are traffic vehicles that continue to come it's able to 141 00:10:03,97 --> 00:10:07,60 extend that minimum green time to give more time to accommodate the traffic that's 142 00:10:07,61 --> 00:10:08,79 coming if there's 143 00:10:08,80 --> 00:10:12,16 a break in traffic that it's going to tell the controller we don't need any more 144 00:10:12,17 --> 00:10:15,80 green time and they'll turn it to yellow and then red and then the side street gets 145 00:10:15,81 --> 00:10:18,23 its turn and that's only if there's 146 00:10:18,24 --> 00:10:21,97 a car on the side street if there's no cars on the side street it'll stay in green 147 00:10:21,98 --> 00:10:28,29 for the main road indefinitely now you talk about minimum green time so what about 148 00:10:28,30 --> 00:10:32,91 the yellow light I notice that sometimes it. Seems 149 00:10:32,92 --> 00:10:38,04 a little quicker than other times and the yellow time is based on the speed of the 150 00:10:38,05 --> 00:10:43,60 approach road so for high speed traffic you might have four or five seconds of 151 00:10:43,61 --> 00:10:44,40 yellow for 152 00:10:44,51 --> 00:10:47,66 a thirty five. Mile an hour road it might only be three seconds but yeah the yellow 153 00:10:47,67 --> 00:10:52,14 time does vary based on the type of roadway that the traffic signals so it's 154 00:10:52,15 --> 00:10:56,01 already doing now you mention there's some different types of detection the 155 00:10:56,02 --> 00:11:00,45 inductive in the camera What are some advantages of one over the other video 156 00:11:00,46 --> 00:11:07,21 detection is easy to use it's. Easier to work 157 00:11:07,22 --> 00:11:10,51 on the loops or in the pavement so if you have to do any work on the pavement you 158 00:11:10,52 --> 00:11:12,56 have to close a lane of traffic it's a it's 159 00:11:12,57 --> 00:11:17,26 a lot more effort to take care of if something goes wrong and something can go 160 00:11:17,27 --> 00:11:21,96 wrong if the pavement is old then the loop may start coming out of the ground or or 161 00:11:22,41 --> 00:11:27,75 break so you can have some problems with maintenance video detection can have 162 00:11:27,76 --> 00:11:33,74 problems in the fog or shadows because they see movement and that it thinks it's 163 00:11:33,75 --> 00:11:37,40 a vehicle so if you have a tree nearby that causes a shadow It may think it's 164 00:11:37,41 --> 00:11:41,61 a vehicle and you might get in might be calling traffic when it doesn't really need 165 00:11:41,62 --> 00:11:47,70 to so you know there are benefits and disadvantages to both types of technology we 166 00:11:47,71 --> 00:11:54,47 use them both now my friend always tells me that white always ignores him is that 167 00:11:54,48 --> 00:11:55,12 true is there 168 00:11:55,13 --> 00:11:59,16 a difference shouldn't I know that you can adjust the sensitivity of the loop 169 00:11:59,17 --> 00:12:00,71 that's in the ground but 170 00:12:00,75 --> 00:12:04,07 a motorcycle has enough metal to it it should it should recognize that it's there 171 00:12:04,08 --> 00:12:09,73 certainly video camera should be able to see it so that shouldn't be the case if we 172 00:12:09,74 --> 00:12:13,14 get that type of complaint we can certainly go look at it and see if the 173 00:12:13,15 --> 00:12:17,81 sensitivity needs to be adjusting We also have similar problems with long trailers 174 00:12:17,82 --> 00:12:23,77 that may have not metal on the trailer but it might be wood and if it's not 175 00:12:24,14 --> 00:12:26,35 a significant metal it might have 176 00:12:26,36 --> 00:12:29,53 a little more difficulty picking it up but again we should be able to adjust the 177 00:12:29,54 --> 00:12:35,65 sensitivity so that's not an issue and how far back from the from the stop line we 178 00:12:35,69 --> 00:12:40,09 were supposed to stop how far back is the inductive loop usually going to be it's 179 00:12:40,10 --> 00:12:40,59 usually 180 00:12:40,76 --> 00:12:45,57 a couple feet behind the stop bar but it's it should be able to. You know if you 181 00:12:45,58 --> 00:12:46,25 pull up past 182 00:12:46,26 --> 00:12:49,90 a stop are it should still pick you up if your way in front of the STOP are there 183 00:12:49,91 --> 00:12:55,16 are times when it won't catch you. So that's why we have the stop are it tells you 184 00:12:55,17 --> 00:12:58,14 where to stop and generally yeah the loop is 185 00:12:58,15 --> 00:13:00,91 a couple feet behind that stop learning should cover 186 00:13:00,92 --> 00:13:05,34 a pretty good range of where folks stop now what are these some of the approximate 187 00:13:05,35 --> 00:13:07,62 costs for these intersections Well there's 188 00:13:07,63 --> 00:13:12,80 a couple different type of intersection you might see. What we've had for many many 189 00:13:12,81 --> 00:13:18,09 years our spanners employees you'll see. Probably four concrete poles and 190 00:13:18,10 --> 00:13:19,48 a gender section that have just 191 00:13:19,49 --> 00:13:22,36 a wire running between with the signal heads on and we call that 192 00:13:22,37 --> 00:13:26,75 a span wire assembly and that's maybe on the order of eighty thousand dollars per 193 00:13:26,76 --> 00:13:32,29 intersection we also have massed arms which are bigger metal structures with big 194 00:13:32,30 --> 00:13:34,91 arms they're about twice the cost maybe 195 00:13:34,92 --> 00:13:39,04 a hundred sixty thousand dollars per intersection part of that's 196 00:13:39,05 --> 00:13:44,30 a static it is more structurally sound it's you certainly want to mirror 197 00:13:44,31 --> 00:13:48,27 a cosigner or you have hurricane force winds that's not as important in Polk County 198 00:13:48,28 --> 00:13:52,35 would be in the southern state but you know they look nice so some maintaining 199 00:13:52,36 --> 00:13:56,95 agencies in certain corridors want you know more aesthetic looks but both of them 200 00:13:56,96 --> 00:14:01,11 function the same for as far as traffic signals and it with obviously with the 201 00:14:01,12 --> 00:14:06,61 growth of the county and the growth of the area when you guys determine there how 202 00:14:06,62 --> 00:14:08,84 do you determine when to put in a new light or to put in 203 00:14:08,85 --> 00:14:13,97 a new intersection Well you know it's based on traffic and traffic needs when we 204 00:14:13,98 --> 00:14:18,10 see that there's an intersection that is approaching you know heavy volumes we 205 00:14:18,11 --> 00:14:22,67 would look at if we have warrants for traffic signals and we're always looking at 206 00:14:22,68 --> 00:14:26,84 the road network and the traffic volumes to improve traffic flow so we're always 207 00:14:26,85 --> 00:14:31,50 keeping an eye on on the traffic to see what improvements we might need to make and 208 00:14:31,51 --> 00:14:34,28 fact the traffic changes impact 209 00:14:34,29 --> 00:14:38,75 a lot of what we do it's part of this division for instance bridges are impacted by 210 00:14:38,76 --> 00:14:43,73 changes in traffic and when they might need to be updated or rebuilt and boy or 211 00:14:43,74 --> 00:14:48,69 a structural engineer I think is ready to talk to about bridges. Or looking over 212 00:14:48,70 --> 00:14:50,33 a I'm with keen 213 00:14:50,34 --> 00:14:53,81 a structural engineer for Polk County can let's start off with the main question 214 00:14:53,82 --> 00:14:58,18 what is a bridge bridge is structurally used to go from one side of 215 00:14:58,19 --> 00:15:03,49 a road or obstacle to another without interfering with the obstacle and what types 216 00:15:03,50 --> 00:15:09,90 of bridges are there. Many types three basic materials that we were with 217 00:15:09,91 --> 00:15:16,84 concrete steel and wood in certain cases and each material then 218 00:15:16,85 --> 00:15:23,64 you get into different design types and beams and. Elements of the bridge and when 219 00:15:23,65 --> 00:15:29,67 you say design types I mean I know this isn't the only style of bridge what are 220 00:15:29,68 --> 00:15:35,16 what are some of the what are some examples Well the in steel you use says we just 221 00:15:35,17 --> 00:15:41,24 have you can have your steel trusses which are much larger structures. The elements 222 00:15:41,25 --> 00:15:44,46 are essentially just made out of steel this bridge here is 223 00:15:44,47 --> 00:15:50,62 a concrete bridge it's pre-stressed beams I believe and it's 224 00:15:50,63 --> 00:15:54,70 a prefabricated beam Also you can actually do cast in place which means you 225 00:15:54,71 --> 00:15:59,92 actually make the forms in place and pour the concrete in place and take forms and 226 00:15:59,93 --> 00:16:05,41 go away and what what goes into this terming you know what the look of the bridge 227 00:16:05,42 --> 00:16:10,58 is going to be like. Economics is always a factor you have 228 00:16:10,59 --> 00:16:15,49 a static reasons you want to do something and then certain bridges are inexpensive 229 00:16:15,50 --> 00:16:18,51 to build quick an easy and entirely durable like 230 00:16:18,52 --> 00:16:23,11 a casting place is one of the basics but the span this span that we have here is 231 00:16:23,12 --> 00:16:29,66 about. Thirty feet so that helps determine what type of bridge is bigger bridges 232 00:16:29,76 --> 00:16:36,48 longer span different elements different beam style sizes and styles how far apart 233 00:16:36,88 --> 00:16:40,62 when you say big or bridge and stuff about what's the rule of thumb for pilots is 234 00:16:40,63 --> 00:16:44,94 their rules for how where the supports are going to be or how does that work out 235 00:16:45,46 --> 00:16:49,95 that's those are design issues the actual design or make those determinations of. 236 00:16:51,01 --> 00:16:55,84 No real rule of thumb is just the longer this man the bigger the beams and the 237 00:16:55,85 --> 00:17:01,72 bigger the pile and bigger everything or the new Like the largest one of course of 238 00:17:01,73 --> 00:17:07,05 the suspension bridges like the cable stays or the Golden Gate We don't have 239 00:17:07,06 --> 00:17:12,55 a need for those around here we don't have any rivers quite that big band are there 240 00:17:12,56 --> 00:17:16,03 any special preparations you do I know we're in Florida hurricanes 241 00:17:16,04 --> 00:17:19,45 a lot of storms and something or other special preparations you do special 242 00:17:19,55 --> 00:17:25,83 procedures you have for for building the bridge or to help it withstand those. What 243 00:17:25,84 --> 00:17:30,57 you just describe are just. Different loads in 244 00:17:30,58 --> 00:17:36,04 a long list of loads you know the one thing the bow bridges they are designed to 245 00:17:36,05 --> 00:17:42,09 carry traffic loads which is your cars and trucks and buses and and cranes and 246 00:17:42,10 --> 00:17:48,74 anything else that goes on the road motorcycles and bicycles also. The hurricane 247 00:17:48,75 --> 00:17:52,75 is gives you the win load in the else have water loads water is 248 00:17:52,76 --> 00:17:58,91 a load it rises and falls and it can be quite severe sometimes given the hurricane 249 00:17:58,92 --> 00:18:05,75 load as is is brings the wind in the rain and it's just. Several of the 250 00:18:05,76 --> 00:18:12,42 long list of lows that we have to deal with and. One that we see 251 00:18:12,43 --> 00:18:13,19 mostly is 252 00:18:13,20 --> 00:18:19,68 a flood issue and flood is rising waters century by definition it's not really rain 253 00:18:19,69 --> 00:18:26,61 coming down the rising water and so on canals and creek and road crossings they 254 00:18:26,62 --> 00:18:31,22 may or may not get clogged fellow bridges bigger the bridges get 255 00:18:31,23 --> 00:18:36,28 a larger opening the smaller ones. From my dog standpoint you might build 256 00:18:36,29 --> 00:18:37,37 a culvert will be called 257 00:18:37,38 --> 00:18:43,28 a culvert which is they're essentially relatively speaking small they might be 258 00:18:43,29 --> 00:18:49,30 eight to ten feet wide or several We call them barrel several openings the problem 259 00:18:49,31 --> 00:18:55,49 that they have is large flows they tend to collect dirt and trash and debris trash 260 00:18:55,50 --> 00:19:00,02 bin you know trees and sticks and everything and the sediment will build up and 261 00:19:00,03 --> 00:19:01,78 they do tend to clog a lot quicker than 262 00:19:01,79 --> 00:19:07,95 a bridge will go and what do you how do you maintain or how do you maintain that 263 00:19:08,49 --> 00:19:13,04 the coverts basically just have to go in clean amount. You know with machinery or 264 00:19:13,05 --> 00:19:13,65 man or 265 00:19:13,77 --> 00:19:18,10 a little bit of both and somebody might have to get what is there as their regular 266 00:19:18,11 --> 00:19:21,54 schedule or is it you have an extra inspector goes around and check the bridges are 267 00:19:21,55 --> 00:19:27,18 and how that works well the bridges if it's there on the bridge lifts you know by 268 00:19:27,19 --> 00:19:32,55 definition a bridge is twenty feet from side to side they're on 269 00:19:32,56 --> 00:19:39,15 a regular two year inspection program and. The reports indicate if there's an 270 00:19:39,16 --> 00:19:41,15 issue and we go out and check 271 00:19:41,16 --> 00:19:45,75 a mountain if there's an issue we. Face public safety is 272 00:19:45,76 --> 00:19:52,06 a big thing we provide the for public safety the traveling public and if it becomes 273 00:19:52,07 --> 00:19:55,38 a safety issue we take care of it right away regular maintenance is regular 274 00:19:55,39 --> 00:20:02,38 maintenance you know they. Trash and debris cumulate so you can. That clean it up 275 00:20:02,39 --> 00:20:07,08 when you when it's on your schedule to do so all right. Now tell me 276 00:20:07,09 --> 00:20:10,36 a little bit about the the design of this specific bridge that we're staying here 277 00:20:10,37 --> 00:20:12,59 just so I can get a better understanding of how 278 00:20:12,63 --> 00:20:18,39 a bridge going with the canal wouldn't wait it would get put in OK. Well this 279 00:20:18,40 --> 00:20:24,61 bridge it's basically thirty feet from side to side. It was it's been here since 280 00:20:24,62 --> 00:20:29,08 about one thousand nine hundred eighty the this canal actually provides for boat 281 00:20:29,09 --> 00:20:34,34 traffic so another factor we have to consider is. Make sure there's enough water in 282 00:20:34,35 --> 00:20:34,68 here for 283 00:20:34,69 --> 00:20:40,59 a boat to pass because they do fill in and you have to dredge and. Once you set the 284 00:20:40,60 --> 00:20:45,98 span the design will start to span cording the criteria given by the canal boat for 285 00:20:46,34 --> 00:20:52,75 the traffic requirements and then you can calculate loads in that you know each 286 00:20:52,76 --> 00:20:56,66 element has its own capacity so you design you choose 287 00:20:56,67 --> 00:21:01,09 a number of like piles you see the piles underneath on each side you choose 288 00:21:01,10 --> 00:21:04,93 a number of those based on each capacity and we also have to do 289 00:21:04,94 --> 00:21:09,82 a geotechnical investigation which means we send in another engineer different kind 290 00:21:09,83 --> 00:21:12,35 of engineer and he actually drilled 291 00:21:12,36 --> 00:21:17,33 a hole probably about eighty five feet deep to find out what kind of soil is 292 00:21:17,52 --> 00:21:22,42 underneath where we're standing up because that's what we're going to use to hold 293 00:21:22,43 --> 00:21:27,65 the bridge up and it is the obviously you can't really get rid of the water you 294 00:21:27,66 --> 00:21:30,76 just have to deal with the added work around that well in this bridge and we did 295 00:21:30,77 --> 00:21:36,82 all this work. There was no boat traffic because we dam that can now OK so about 296 00:21:36,83 --> 00:21:38,18 where I we were standing we had 297 00:21:38,19 --> 00:21:45,09 a twenty foot. Tall polished dirt and some sheet piles to block off the water so 298 00:21:45,10 --> 00:21:49,31 the guys when they're working we're actually working in the dry OK under certain 299 00:21:49,32 --> 00:21:53,77 conditions you can do that other conditions you just have to work in the water all 300 00:21:53,78 --> 00:21:58,08 right now I know obviously with the water here and stuff it's going to erode away 301 00:21:58,09 --> 00:22:02,18 and it's going to cause some deterioration and what goes into an inspection for 302 00:22:02,19 --> 00:22:07,79 a bridge like this to make sure that it's still you know that stable OK well this 303 00:22:07,80 --> 00:22:08,87 bridge is 304 00:22:08,88 --> 00:22:15,20 a small bridge but amazingly enough it does have all the parts and so on and since 305 00:22:15,21 --> 00:22:20,90 we're over canal and see the canal here. Water is very corrosive believe it or not 306 00:22:20,97 --> 00:22:26,40 and it will dissolve anything and everything in the inspection with water here we 307 00:22:26,41 --> 00:22:30,05 would actually send divers out and they would go down to the bottom of the canal 308 00:22:30,58 --> 00:22:34,90 and look at the elements are actually in the water and in our case we have the 309 00:22:34,91 --> 00:22:40,68 concrete piles and this deal back wall which is the black that you see. 310 00:22:41,89 --> 00:22:47,44 And we also have a boat coming through and the boat actually creates 311 00:22:47,45 --> 00:22:53,74 a force on the bridge also. Now speaking of loads there's obviously in the news 312 00:22:53,95 --> 00:22:58,14 you've been reporting the stuff about some bridges being structurally deficient How 313 00:22:58,15 --> 00:23:02,48 do you go about rating those and determining when they need maintenance or how 314 00:23:02,49 --> 00:23:07,54 serious the maintenance is going to be well the those terms in the ratings actually 315 00:23:07,55 --> 00:23:14,38 come out of the inspections the the the regular inspections and. The structural 316 00:23:14,39 --> 00:23:15,46 deficiency is 317 00:23:15,47 --> 00:23:20,22 a reflection of the capacity of the bridge to still do its job which is carry 318 00:23:20,23 --> 00:23:26,76 traffic across the obstacle safely to the. You lose your 319 00:23:26,77 --> 00:23:31,99 sufficiency by deteriorating you know concrete gets old and soft and the steel 320 00:23:32,00 --> 00:23:38,61 inside will rust and cause you know problems with the bridge you know regular steel 321 00:23:38,62 --> 00:23:42,38 bridges steel itself or ROSS You know I mean it's on the steel bridge is clean and 322 00:23:42,39 --> 00:23:48,32 painting on a regular basis and so it is a it's actually 323 00:23:48,33 --> 00:23:54,78 a calculated number and you can recalculate the capacity of the beam or the 324 00:23:54,79 --> 00:24:00,17 bridge in its new condition as opposed to its use condition you know new condition 325 00:24:00,18 --> 00:24:04,20 be in thirty to forty years after it was built it's 326 00:24:04,21 --> 00:24:09,31 a current condition that we're in and that's what we look at for the repairs and 327 00:24:09,32 --> 00:24:14,62 what's wrong with the bridge and can this repair extend the life of the bridge or 328 00:24:14,95 --> 00:24:18,67 at some point we actually do evaluation do we need to just replace the bridge 329 00:24:18,68 --> 00:24:24,85 rather than continue to spend money to fix an old tired bridge now you mention with 330 00:24:24,86 --> 00:24:29,71 the main maintaining the steel bridges it repainting in and helping take care of 331 00:24:29,72 --> 00:24:34,71 some of that rust and stuff is there anything special you do to help prolong the 332 00:24:34,72 --> 00:24:35,19 life of 333 00:24:35,52 --> 00:24:42,39 a concrete bridge. Nothing not that obviously simple but essentially we do the same 334 00:24:42,40 --> 00:24:45,76 thing we can you know concrete you'll notice they get black and everything else 335 00:24:45,77 --> 00:24:50,34 just mold and stuff so we we can actually come in and clean and paint and the pain 336 00:24:50,35 --> 00:24:50,77 acts as 337 00:24:50,78 --> 00:24:57,72 a SEAL or what deteriorates bridges rapidly relatively speaking is again it's water 338 00:24:58,17 --> 00:25:02,78 whether it's rain water or sea water or whatever kind of water and 339 00:25:02,100 --> 00:25:09,95 a good concrete is not waterproof so it water will penetrate and this get to the 340 00:25:09,96 --> 00:25:15,52 steel in the steel will eventually rust and so we clean and paint that helps us we 341 00:25:15,78 --> 00:25:20,71 mostly with concrete you seal it if it has broken areas where it's cracked and 342 00:25:20,72 --> 00:25:26,32 stuff you chip off the loose concrete you can we have high tech mortars and stuff 343 00:25:26,71 --> 00:25:32,73 that will stick and seal it back off and we essentially just packed it all right so 344 00:25:32,77 --> 00:25:35,30 obviously you can maintain it above but I know 345 00:25:35,31 --> 00:25:39,65 a lot of the bridge is underneath is down the water you know right there where the 346 00:25:39,66 --> 00:25:46,38 water is how hot how do you help prolong it well same idea 347 00:25:46,58 --> 00:25:52,66 in on this bridge you can see along the side there's the five red squares those are 348 00:25:52,67 --> 00:25:58,69 the piles and what we did in this case the piles have been sitting in the water for 349 00:25:58,81 --> 00:26:03,90 however long twenty to thirty years and as I said before water is extremely 350 00:26:03,91 --> 00:26:08,37 corrosive and so what we do with the piles is we essentially come just put 351 00:26:08,38 --> 00:26:13,40 a jacket around them and that's where you see the larger part and then the very 352 00:26:13,41 --> 00:26:17,70 small part of the top is the original pile the larger part of it is just like you 353 00:26:17,71 --> 00:26:18,14 putting on 354 00:26:18,15 --> 00:26:22,34 a jacket because it's cold out we put jackets on here to keep the water off of the 355 00:26:22,35 --> 00:26:28,31 structural part of the pile and the black wall behind the piles. In this bridge 356 00:26:28,32 --> 00:26:33,40 that was entirely replaced because it used to be. New Porsche 357 00:26:33,41 --> 00:26:37,86 a new steel that was essentially rusted through several spots and it could no 358 00:26:37,87 --> 00:26:43,53 longer hold the soil up behind it those are all new and we coat the steel with 359 00:26:44,24 --> 00:26:49,29 a coating just to stop it from rusting and it will that what we did here is 360 00:26:49,30 --> 00:26:50,11 a it has 361 00:26:50,12 --> 00:26:55,91 a design life not intended to last forever but it'll be fifty sixty years before we 362 00:26:55,92 --> 00:27:01,13 have to actually come out and give it some serious attention again because now I 363 00:27:01,14 --> 00:27:02,81 notice on this bridge there's a there's 364 00:27:02,82 --> 00:27:07,94 a drain popping Elo What's that go to with that help out with OK Well those are. 365 00:27:09,25 --> 00:27:10,86 You referring to though P.V.C. 366 00:27:10,87 --> 00:27:16,02 Pipe sticking out through the walls Those are just drains because we don't want 367 00:27:16,03 --> 00:27:19,55 water to build up behind the wall because if the water builds up that's 368 00:27:19,56 --> 00:27:23,73 a tremendous load on the wall and it also would tend to wash with the dirt out from 369 00:27:23,74 --> 00:27:29,64 behind us so we put drains into. The tent of the storm is hydrostatic pressure we 370 00:27:29,65 --> 00:27:35,55 put the drains in to relieve the hydrostatic pressure tank and so the small simple 371 00:27:35,61 --> 00:27:39,70 but very important now obviously we talk about maintaining the bridges about how 372 00:27:39,71 --> 00:27:43,90 many bridges throughout the county do you have to take care of are you responsible 373 00:27:43,91 --> 00:27:49,23 for while I take care of the Polk County bridges that Polk County actually owns 374 00:27:49,81 --> 00:27:54,42 many bridges are owned by the state but the Polk County is the proud owner of about 375 00:27:54,43 --> 00:27:59,00 one hundred eighty four bridges and it varies because we're building new ones on 376 00:27:59,01 --> 00:28:03,27 occasion we actually tear one or two down the no longer necessary and there's 377 00:28:03,28 --> 00:28:07,37 another way that they can go. It's quite 378 00:28:07,38 --> 00:28:13,53 a number of bridges the good thing is most if not all are in generally good shape 379 00:28:14,01 --> 00:28:14,45 you get 380 00:28:15,03 --> 00:28:19,24 a good well thank you so much for bringing out here let me know your brain about 381 00:28:19,25 --> 00:28:23,68 the bridges was my pleasure Brad thank you well that's all we have for today join 382 00:28:23,69 --> 00:28:26,45 us next time as we see got yet another science question.